Sample conditioning unit



Oct. 24, 1967 o. TRAVAGLIO SAMPLE CONDITIONING UNIT Filed Feb. 27, 19642 Sheets-Sheet all/ r ATTORNEYS n 9 a a 4 7 3 2 1 7 M 3 4 M M 1/ .n M mJ an E w m HQ Q 2 z I 3 4 D. TRAVAGLIO SAMPLE CONDITIONING UNIT Oct. 24,1967 2. Sheets-Sheet 2 Filed Feb. 27, 1964 INVENTOR- DALNY TEAVAGL/Oarrokugys v United States Patent 3,348,691 SAMPLE CONDITIONING UNITDalny Travaglio, Kensington, Califi, assignor, by mesne assignments, toWarner-Lambert Pharmaceutical Company, Morris Plains, NJ.

Filed Feb. 27, 1964, Ser. No. 347,787 9 Claims. (Cl. 210-255) ABSTRACTOF THE DISCLOSURE This invention provides a sample conditioning unitespecially designed to filter samples analyzed in automatic analyticapparatus, with the unit being a relatively inexpensive plastic blockconstruction providing a plurality of side-by-side chambers suitable forholding samples during preliminary steps and a filtering chamber adaptedto hold a filter; the block being constructed with a passage formed inthe housing of the block in such way that the passage extends from thebottom of one chamher to a central location at the top of the chamberadapted to carry out the filtering, and with the filtering chamber beingremovable for easy access to clean the unit and re place the filter.

The present invention relates to improvements in a sample conditioningunit, and more particularly to such a unit adapted to provide aseparation of a component in automated analytical equipment.

Many types of chemical analyses require the processing of a great numberof samples of similar character. The repetitive performance of similaroperations lends itself to automation, and the use of automaticanalyzing equipment can result in a material savings in the time of theoperator. In addition, the automated equipment provides more uniformprocedures with greater accuracy and greater economy through theunattended operation.

However, it is important to use definite fixed analytical procedures forcarrying out the analyses, and these procedures are carefully worked outto provide a standard which is of value to the person interpretingtheanalytical results. Accordingly, it is important to adhere to thestandards, and therefore certain steps which have been difficult toautomate in simple equipment must be automated in order to achieve theobjectives of the present invention.

One of the steps often used in analytical procedures is the separationof a constituent of a sample, and a typical procedure involves theprecipitation and filtration of the constitutent. It has been proposedto effect such separation -by means of automated centrifuging devices,but such a unit requires a rather complicated mechanism.

In order to provide a unit suitable for automated analytic equipmentwhere filtering or conditioning is achieved by passing the samplethrough filter paper or other media, a sample conveying and conditioningunit has been developed which is the subject of a copending UnitedStates patent application Ser. No. 207,122 filed July 2, 1962, nowpatent number 3,282,431, by Hans Baruch and Dalny Travaglio, andassigned to the same assignee as the present invention. While theapplication cited above describes a unit which is eminently satisfactoryfo'f its purpose, it has been found that certain improvement may be madethereon, and the present invention is directed to such improvements.

In its preferred form, the invention relates to an improved filteringdevice suitable for automatic filtration,

Patented Oct. 24, 1967 but in its broad form, other means forconditioning sample as it passes therethrough can be used. For example,an ion exchange resin could be used to effect a desired change on thesample, or the sample could be contacted with activated charcoal or anactivated refractory material or ceramic filter to remove certainmaterials from the sample. The sample may also be treated with filteraids such as diatomaceous earth.

The invention also provides a unit where precipitation or othertreatments are effected while the unit is conveyed through an automatedsystem, and this provides a cont-rol of the time duration, and allowsfor other treatments to be provided by the automated equipment. A morecomplete disclosure of automated equipment which may use the sampleconveying and conditioning unit of this invention is given in thecopending United States patent application cited above and theapplications cited therein. Accordingly, this structure will not bedescribed in detail herein.

It is a primary object of this invention to provide an improved unitcapable of conveying and conditioning samples, and particularly a unitcapable of separating constituents from samples as they are carriedthrough analytical procedures in an automated analytical system, inWhich an improved transfer of sample is provided together with decreasedcross-contamination between samples.

Another object of the invention is the provision of an improved unit ofthe character described which is capable of providing a rapid filtrationin an automated system in a manner similar to the operation conducted bya laboratory technician using manual procedures.

A further object of the invention is the provision of a unit of thecharacter described which is composed of a material that is resistant tochemicals, and which is capable of a long useful life.

A still further object of the invention is to provide a sample conveyingand conditioning unit which is constructed in parts to provide easyfabrication and improved cleaning, and which can be fitted with a newfilter or the like when necessary between operations.

Further objects and advantages of my invention will appear as thespecification continues, and the new and useful features of my sampleconditioning unit will be fully defined in the claims attached hereto.

The preferred forms of my invention are illustrated in the accompanyingdrawings, forming part of this description, in which:

FIGURE 1 is a plan view of a preferred form of a sample conditioningunit constructed according to the invention as it appears in operationwith automatic equipment;

FIGURE 2, a sectional view of the apparatus shown in FIGURE 1 takensubstantially in the plane of line 22 thereof;

FIGURE 3, a perspective view of the components of a filter blockconstructed according to the invention and utilized as a component ofthe apparatus shown in FIG- URES 1 and 2;

FIGURE 4, a sectional view of a portion of the filter block shown inFIGURES 1 through 3 taken substantially in the plane of line 4-4 ofFIGURE 2; and

FIGURE 5, a sectional view of a portion of the filter block shown inFIGURES 1 through 3 taken substantially in the plane of line 55 ofFIGURE 2.

While I have shown only the preferred forms of my invention, it shouldbe understood that various changes or modifications may be made withinthe scope of the claims hereto attached, without departing from thespirit of the invention.

Referring to the drawing in greater detail, there is shown in FIGURE 1 asample conditioning unit 11, comprising one or more filter blocks 12each having a plurality of laterally spaced open top compartmentsserving as sample containers, a sample conditioning means, and means fortransferring sample from one container to another. The filter blocks maybe made of any suitable material, but they are preferably molded from amoldable plastic.

Thus, in the preferred form, the filter blocks 12 are each in the formof a unit having four open top containers or compartments adapted tohold sample material. Container 13 is adapted to receive samples, andthe samples are moved progressively across the unit through compartments14, 16 and 17 as hereinafter explained. Various treatments may beeffected on the sample as it moves laterally across the unit, and aseparation is carried out as the sample moves from container 16 tocontainer 17.

As best seen in FIGURE 3, the filter blocks 12 are preferably molded intwo sections including an upper section 18 and a lower section 19. Thisconstruction has the advantage of allowing easy replacement of filtercups 21a within container or compartment 16. In addition, it allows foreasy fabrication by molding and better access for cleaning.

In order to hold the two sections together, lugs 22 on the upper sectionare force fit into holes 23 in the lower section to provide the basicfilter block 12. These blocks can be secured together, if desired, toprovide larger block units similar to those illustrated in the patentcited above, by fitting connecting rods (not shown) or other fasteningmeans through holes 24 and tying the units together in side-by-sidefashion.

The lower block 19 has supports 26 adapter to ride on a conveyor orslide on a track, and depending lugs 27 adapted to fit in engagementwith a drive chain or the like to provide accurately indexed driving ofthe block units. As here shown, a dummy container 25 is also provided,and although it serves no function in the embodiment here shown, otherthan for reinforcement, it may be used as a container in otherapplications.

In a typical operation, the samples are conveyed linearly through aplurality of sample stations by a suitable conveyor means, and thetreatments necessary to provide the desired analytical procedures arecarried out. Preferably, the samples are moved stepwise and thetreatments are spaced at selected positions to time the periodbetweenoperations, as disclosed more completely in the copending UnitedStates patent cited above.

As best seen in FIGURE 2, the units are carried on rollers 28, andmovement is imparted to the unit by chain 29 which engages lugs 27 onthe bottom of the blocks 12. The samples are generally loaded into thecompartments or containers 13, and a measured quantity of sampletransferred to container 14 along with a precipitating reagent in atransfer device (not shown). The slurry is then transferred intofiltering position by a transfer device 31.

The transfer device 31 comprises a support 32 which is adjustable topresent the device at any'desired sample station, and a cylinder 33carried by the support and. adapted to move vertically into and out ofposition on container 14 and provide positive pressure therein foreffecting transfer of liquid to compartment 16 through connectingchannel 34. This connecting channel is an important feature of thepresent invention because it improves the system show in the priorpatent cited above by reducing cross-contamination between samples andsimplifying the construction of transfer device 31.

In the prior patent, an-inverted U-tube was used in combination with apressure head to effect this transfer.

This required a longer stroke of the pressure head in order to move theU-tube end axially from the bottom of the tube to a clearance position.In addition, the U-tube was not always cleaned between handling of eachsample, and therefore, the system was. restricted in applicability. Bothof these problems are solved in the present invention.

The connecting channel 34 is constructed to extend from the bottom ofcontainer 14 to a discharge position 36 centrally located in the upperportion of compartment 16. In this way, material is discharged intofilter cup 21 where rapid filtration occurs. Preferably the compartment14 has sloping walls which form a well 37 in communication withconnecting channel 34. This allows for rather complete transfer ofliquid. If desired, suitable reinforcing structure can be included suchas ribs 38, but it is important to fabricate the ribs in such a way thatthey do not interfere with proper movement of sample.

The cylinder 33 of transfer device 31 comprises a plunger 39 slidablymounted therein so as to move between a sealing position and a clearanceposition over compartment 14. Plunger 39 has a lower surface 41 adaptedto fit in sealing engagement with the top of the container 14 so that ondownward movement of the plunger a positive pressure may be applied inthe container by controlled air movement through a passage 42 extendingthrough the bottom of the plunger and providing an orifice in thepassage. The orifice passage is small enough that a positive pressurebuilds up within the cylinder to retain downward movement against thespring 43. The orifice also prevents excess pressure from building up incontainer 14.

In operation, air pressure is provided through line 44, which pressurecauses plunger 39 to move downward. As the plunger 39 moves downward,the surface 41 thereof provides a seal in the container 14, and air thenpasses from within the cylinder 33 down through the or-ifice into thecontainer to provide a super-atmospheric pressure therein. This pressurethen causes liquid to be forced through tube connecting channel 34 sothat substantially all of the liquid is removed and forced into thefilter cup 21 of compartment 16. When the air pressure is shut off inline 44, the super-atmospheric pressure within the cylinder and withinthe container is soon reduced and spring 43-forces the plunger 39 backto the clearance position. In this way, the plunger and tube arewithdrawn so that the unit 11 may be advanced to the next station.

The slurry delivered into the filter cup 21 passes through the filterand down through a passage 46 into compartment 17. The filter cup 21 isheld in the compartment 16 by a sloping floor 47 and axially extendingribs 48. In this way all of the walls of the filter cup assist toprovide rapid filtration. Thus separation is effected between the solidprecipitate and the liquid filtrate, and the filtrate is carried in thecompartments 17 for further treatment and/or transfer to other pieces ofequipment for completion of the analysis.

In the unit here shown, the filter cup 21 is constructed of porous paperso that rapid filtration takes place by gravity, and external pressureis not needed. However, it will be appreciated that positive pressurecould also be applied to speed up filtration, if desired. Filter cups inthe form of that shown in FIGURE 2 are available through regularcommercial supply channels, and these units are quite suitable. Ifdesired, cups may be fabricated from ordinary filter paper to providethe cup 21 shown in FIGURE 3.

As indicated above, the four compartments are cleaned betweenoperations, and enough filter blocks 12 are provided so that automatedprocedure may be conducted continuously, if desired. When the blocks arecleaned, they are broken down into the two sections and the used filtercups discarded. After cleaning, a new filter cup is placed in eachchamber 16, and the two sections fit to gether. The assembled sectionsthen retain the cup in position until use. The ribs 48 in compartment 16hold the filter cups away from the chamber wall so that unimpededmovement of filtrate is assured through a large filter surface.

From the above description, it is seen that I have provided a filterunit or the like suitable for use in automated analytical systems. It isalso apparent that the unit is simple in construction, and is capable ofconducting a filtering step in an automated system in a manner analogousto the manner in Which a laboratory technician would carry out the sameoperation manually.

I claim:

1. A sample conditioning unit for automated analytical apparatus,comprising a housing having a plurality of laterally spacedcompartments, a first passage in said housing extending from the bottomof a first of said compartments to a location near the top of a secondof said compartments, each of said first and second compartments beinglaterally disposed to each other and defined by walls internal of saidhousing, the walls of said first and second compartments defining saidfirst passage, means for moving liquid through said first passage, asecond passage in communication between said second compartment and athird compartment for carrying liquids from the second to the thirdcompartment, and conditioning means carried in said second compartment.

2. A sample conditioning unit for automated analytical apparatus,comprising a housing having a plurality of laterally spacedcompartments, a first passage in said housing extending from the bottomof a first of said compartments to a location near the top of a secondof said compartments, each of said first and second compartments beinglaterally disposed to each other and defined by walls internal of saidhousing, the walls of said first and second compartments defining saidfirst passage, a pressure supply device mounted for movement intoposition on the first compartment to pressurize the compartment andforce liquid in the first compartment through said passage to the secondcompartment, a second passage in communication between said secondcompartment and a third compartment for carrying liquids from the secondto the third compartment, and conditioning means carried in said secondcompartment.

3. The sample conditioning unit defined in claim 2, in which the housingis composed of a molded plastic containing two sections constructed toprovide improved access to the compartments and passages of the unit.

4. A sample conditioning unit for automated analytical apparatus,comprising a housing having a plurality of laterally spacedcompartments, a first passage in said housing extending from the bottomof a first of said compartments to a location near the top of a secondof said compartments, each of said first and second compartments beinglaterally disposed to each other and defined by walls internal of saidhousing, the walls of said first and second compartments defining saidfirst passage, means for moving liquid through said first passage, asecond passage in communication between said second compartment and athird compartment for carrying liquids from the second to the thirdcompartment, and a cupshaped filter carried in said second compartmentin position to receive liquid from said first passage.

5. A sample conditioning unit for automated analytical apparatus,comprising a housing having a plurality of laterally spacedcompartments, a first passage in said housing extending from the bottomof a first of said compartments to a location near the top of a secondof said compartments, each of said first and second compartments beinglaterally disposed to each other and defined by walls internal of saidhousing, the walls of said first and second compartments defining saidfirst passage, a

pressure supply device mounted for movement into position on the firstcompartment to pressurize the compartment and force liquid in the firstcompartment through said passage to the second compartment, a secondpassage in communication between said second compartment and a thirdcompartment for carrying liquids from the second to the thirdcompartment, a cup-shaped filter carried in said second compartment inposition to receive liquid from said first passage, and a plurality ofaxially extending ri-bs on the wall of said second compartment forholding the cup-shaped filter away from the walls of the compartment andimprove drainage of liquid that has passed through the filter.

6. A sample conditioning unit for automated analytical apparatus,comprising a housing having a plurality of laterally spacedcompartments, a first passage in said housing extending from the bottomof a first of said compartments to a location near the top of a secondof said compartments, each of said first and second compartments beinglaterally disposed to each other and defined by Walls internal of saidhousing, the walls of said first and second compartments defining saidfirst passage, a pressure supply device mounted for movement intoposition on the first compartment to pressurize the compartment andforce liquid in the first compartment through said passage to the secondcompartment, said pressure supply device including a cylinder having acontrolled supply of compressed air and a plunger movable onto saidsecond compartment when the cylinder is pressurized, said plunger havinga restricted passage for supplying air at a controlled air pressure inthe second compartment, a second passage in communication between saidsecond compartment and a third compartment for carrying liquids from thesecond to the third compartment, and a cup-shaped filter carried in saidsecond compartment in position to receive liquid from said firstpassage.

7. The sample conditioning unit defined in claim 6 in which the housingis composed of a molded plastic containing two sections constructed toprovide improved access to the compartments and passages of the unit.

8. A sample conditioning unit for automated analytical apparatus,comprising a housing constructed in two sections including an uppersection and a lower section, a plurality of compartments in said uppersection including a first open top compartment and a second compartmentlaterally disposed to the first compartment and having an open bottom, afirst passage in said housing. extending from the bottom of the firstcompartment to a central location at the top of the second compartment,each of said first and second compartments defined by walls internal ofsaid housing, the walls of said first and second compartments definingsaid first passage, a pressure supply device mounted for movement intoposition on the first compartment to pressurize the compartment andforce liquid in the first compartment through said passage to the secondcompartment, a cup-shaped filter carried in said second compartment inposition to receive liquid from said first passage, and a thirdcompartment in said lower section in position to receive liquid passingthrough the filter in said second compartment.

9. A sample conditioning unit for automated analytical apparatus,comprising a housing constructed in two sections including an uppersection and a lower section, a plurality of compartments in said uppersection including a first open top compartment and a second compartmentlaterally disposed to the first compartment and having an open bottom, afirst passage in said housing extending from the bottom of the firstcompartment to a central location at the top of the sec-ond compartment,each of said first and second compartments defined by walls internal ofsaid housing, the walls of said first and second compartments definingsaid first passage, a pressure supply device mounted for movement intoposition on the first compartment to pressurize the compartment andforce liquid in the first compartment through said passage to the secondcompartment, said pressure supply device including a cylinder having acontrolled supply of compressed air and a plunger movable onto saidsecond 7 8 compartment when the cylinder is pressurized, said ReferencesCited plunger having a restricted passage for supplying air at UNITEDSTATES PATENTS a controlled air pressure in the second compartment, acup-shaped filter carried in said second compartment in 116,515 6/1871Weare 210-255 position to receive liquid from said first passage, 3 1 5579,098 3/1897 Srpa1e 2l0203 X rality of axially extending ribs on theWall of said sec- 3 3 32 1,17/1899 Rledel et 4 0nd Compartment forholding the cup-shaped filte away ,19 1 1965 Baruch 23-230 X from thewalls of the compartment and improve drainage 3193359 7/1965 Baruch et23253 X of liquid that has passed through the filter, and a third3282431 11/1966 Baruch 219-474 X compartment in said lower section inposition to receive liquid passing through the filter in said second com10 REUBEN FRIEDMAN Pr'mary Exammerpartment. D. M. RIESS, AssistantExaminer.

1. A SAMPLE CONDITIONING UNIT FOR AUTOMATED ANALYTICAL APPARATUS,COMPRISING A HOUSING HAVING A PLURALITY OF LATERALLY SPACEDCOMPARTMENTS, A FIRST PASSAGE IN SAID HOUSING EXTENDING FROM THE BOTTOMOF A FIRST OF SAID COMPARTMENTS TO A LOCATION NEAR THE TOP OF A SECONDOF SAID COMPARTMENTS, EACH OF SAID FIRST AND SECOND COMPARTMENTS BEINGLATERALLY DISPOSED TO EACH OTHER AND DEFINED BY WALLS INTERNAL OF SAIDHOUSING, THE WALLS OF SAID FIRST AND SECOND COMPARTMENTS DEFINING SAIDFIRST PASSAGE, MEANS FOR MOVING LIQUID THROUGH SAID FIRST PASSAGE, ASECOND PASSAGE IN COMMUNICATION BETWEEN SAID SECOND COMPARTMENT AND ATHIRD COMPARTMENT FOR CARRYING LIQUIDS FROM THE SECOND TO THE THIRDCOMPARTMENT, AND CONDITIONING MEANS CARRIED IN SAID SECOND COMPARTMENT.